Climate change: evidence review in Agriculture, Forestry, Land Use, Waste

1 Appendix A1. Qualitative assessment of the wider impacts of ALULUCF GHG mitigation options

A1.1 Developing on-farm renewable energy sources ( MO1)

This MO reduces GHG emissions by increasing small scale renewable energy generation on farms, including wind and solar energy and biomass boilers ( AD is discussed in Section A1.4).

Table 18 Wider impacts of MO1

Mitigation option:		Developing on-farm renewable energy sources ( MO1)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	0	Across all farm scale renewable technologies this is unlikely to be an important impact, however, biomass burning can increase NH 3 emissions.	Saidur et al. 2011
WI2	Air quality: NO x	+	A positive effect as combustion processes are replaced by renewable energy sources (apart from biomass combustion based renewables).	RoTAP 2012
WI3	Air quality: PM	+	A positive effect in reducing particulate emissions as combustion processes are replaced by renewable energy sources (apart from biomass combustion based renewables).	RoTAP 2012
WI4	Air quality: other	+	A reduction in NO x reduces the secondary pollutant formation of ground level ozone.	Gonzalez-de-Soto et al. 2016
WI5	Water quality: Nitrogen leaching	0	No evidence found, unlikely to be a significant impact.
WI6	Water quality: Phosphorous	0	No evidence found, unlikely to be a significant impact.
WI7	Water quality: other	0	For renewables, such as hydro schemes, legislation such as Water Framework Directive and River Basin Management Plans, provide appropriate guidance and help to limit the impact on the water environment.	Copestake 2006
WI8	Soil quality	+/-	More research is required to determine the impact of solar developments on plant-soil carbon recycling. The effect of wind farms varies depending on terrestrial setting of schemes.	Armstrong et al. 2014 Nayak et al. 2008, Nayak et al. 2010, Smith et al. 2011
WI9	Flood management, water use	0	No evidence found, unlikely to be a significant impact.
WI10	Land cover and land use	-	Renewable schemes tend to take up larger areas of land for the amount of power produced compared to conventional energy generation and fossil fuels.	Bergmann et al. 2006
WI11	Biodiversity	0/-	No direct on-farm biodiversity effect is expected. Indirect positive effect though reduced air pollution is expected. Conflicts are likely to increase between energy developments and biodiversity as the number of schemes increase, for example regarding freshwater pearl mussels.	RoTAP 2012 Young et al. 2010 Addy et al. 2012
WI12	Animal health and welfare	0	No evidence found, unlikely to be a significant impact.
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	+	Farmers' income: boost to household income through incentive payments from government environmental programmes such as Feed in Tariffs. Recent government changes to incentive schemes could impact this. Income distribution: no significant impact is expected, though the distribution of the positive impact might be uneven as less prosperous farms might not be able to find the capital for the investment.	Cherrington et al. 2013 Phimister and Roberts 2012
WI15	Consumer and producer surplus	+/-	Varied results depending on siting and type of development. Increase to electricity prices reduces consumer utility.	Bergmann et al. 2006
WI16	Employment	+	Diversification of farm business and increase in employment opportunities and job retention. Impacts can depend on use of additional incomes.	Bergmann et al. 2008, Phimister and Roberts 2011
WI17	Resource efficiency	+	Renewables reduce the need for non-renewable energy generation.
WI18	Human health	+/-	Positive indirect effect through reduced air pollution. Potential negative effect from the noise of small and micros scale wind turbines.	Haines et al. 2006 Taylor et al. 2013
WI19	Social impacts	+	Community ownership of renewables (relevant to a number of on-farm projects) leads to a more positive outlook and more locally involved approach to developments than large scale developments. Renewables can lead to the sustainable development of communities across Scotland.	Warren & McFadyen 2010
WI20	Cultural impacts	0	On-farm renewables, due to their small scale, are unlikely to have a considerable impact on landscape or cultural heritage.

A1.2 Increased uptake of precision farming techniques ( MO2)

Precision farming includes management practices and a wide range of technologies which enable the farmer to obtain and analyse more precise information on the soil, crop and animal qualities in order to respond with management specific to the in-field variation or to the individual livestock. Most importantly to GHG emissions these practices can improve how nitrogen and livestock feed resources are used on farm, reducing N ₂O emissions, energy use by machinery, and/or the GHG emission intensity of crop and livestock products (Eory et al. 2015).

Table 19 Wider impacts of MO2

Mitigation option:		Increased uptake of precision farming techniques ( MO2)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	Some potential reduction is associated with improved spatial applications of fertiliser nitrogen. Optimizing the method of spreading can also decrease NH 3 emissions (see Section A1.8).	Novak and Fiorelli 2010
WI2	Air quality: NO x	+	Increased fuel efficiency in machinery can reduce NO x emissions.	Gonzalez-de-Soto et al. 2016
WI3	Air quality: PM	+	See NO x above.	Gonzalez-de-Soto et al. 2016
WI4	Air quality: other	+	A reduction in NO x reduces the secondary pollutant formation of ground level ozone.	Sutton ed. 2011
WI5	Water quality: Nitrogen leaching	+	Potential improvements associated with reduced nitrate losses if the use of Nitrogen fertilisers is more precisely targeted to crop demand.	Clough et al. 2004
WI6	Water quality: Phosphorous	+	Potential improvements associated with reduced phosphate losses if the use of phosphate fertilisers is more precisely targeted to crop demand.	Rains et al. 2001
WI7	Water quality: other	+	Precision pesticide applications would be likely to reduce the overall loss of pesticides to water.	Bajwa et al. 2015
WI8	Soil quality	+	Information on soil wetness and precision management of soil for example through precision fertiliser application would allow the development of spatially explicit management operations which would reduce machinery traffic and thereby contribute to potential improvements in soil quality.	Bajwa et al. 2015, Sylvester-Bradley et al. 1999
WI9	Flood management, water use	+	Can potentially reduce water resources abstraction from wells/rivers if irrigated crops such as potatoes, salad crops, root vegetables and soft fruit are irrigated using precision irrigation systems in conjunction with soil moisture monitoring systems.	http://www.ukia.org/pdfs/switching%20technologies.pdf
WI10	Land cover and land use	0	No evidence found, unlikely to be a significant impact.
WI11	Biodiversity	+	Precision farming can reduce pesticide use and thus improve on-farm biodiversity.	Timmermann et al. 2003
WI12	Animal health and welfare	+/-	Provides opportunities for better health and nutritional monitoring, but may impact on welfare, e.g. robotically milked cows unlikely to be grazed on pastures.	Wathes et al. 2008
WI13	Crop health	+	Provides better opportunity to match fungicide products to disease risk.	Poole and Arnaudin 2014
WI14	Household income	+	Farmers' income: various opinions are represented in the literature. There is an argument that improved technology will allow farmers to generate increased income and hence become more profitable, though on smaller farms the costs can easily outweigh the financial benefits. Income distribution: no significant impact is expected, though the distribution of the positive impact might be uneven as less prosperous farms might not be able to find the capital for the investment.	Rosch and Dusseldorp 2007, MacLeod et al. 2015
WI15	Consumer and producer surplus	+	No evidence found. Higher efficiency can increased the producer surplus for the farmer and, if large scale efficiency improvements reduce the prices of agricultural products that can increase consumer surplus.
WI16	Employment	-	Potential reduction in rural employment given the likelihood that new technologies would replace existing employees (e.g. robotic milking).	Sassenrath et al. 2008
WI17	Resource efficiency	+	Improved resource use efficiency associated with precision management is likely.	Rosch & Dusseldorp 2007
WI18	Human health	+	Potential benefits resulting from reduced nutrient loss to air and water.	Sutton et al. 2011
WI19	Social impacts	+/-	Reduced employment opportunities and the tendency for precision management technology to be associated with higher income employers could potentially reduce social cohesion. If PF machinery is pooled the increased importance of co-ops might improve cohesion.	Sassenrath et al. 2008
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.3 Achieving and maintaining optimal soil pH level ( MO3)

For optimal soil chemistry, nutrient availability and plant growth it is recommended that the pH of arable soils is maintained at 6 or above and that for grassland soils at 5.8 or above ( SRUC 2015). Sub-optimal liming on acidic soils leads to less efficient use of plant nutrients and can also result in a larger proportion of nitrogen applied being released as N ₂O (Baggs et al. 2010).

Table 20 Wider impacts of MO3

Mitigation option:		Achieving and maintaining optimal soil pH level ( MO3)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+/-	Increasing soil pH is likely to increase nitrogen use efficiency, but higher pH can also lead to increases in NH 3 volatilisation.	Goulding 2016
WI2	Air quality: NO x	0	No evidence found, unlikely to be a significant impact.
WI3	Air quality: PM	0	No evidence found, unlikely to be a significant impact.
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+	Increasing soil pH is likely to increase nitrogen use efficiency, which would therefore lead to lower nitrogen leaching.	Goulding 2016
WI6	Water quality: Phosphorous	+	Increasing soil pH generally reduces the availability of phosphate in soils and therefore reduces the leaching risk	Goulding 2016
WI7	Water quality: other	+	Possible reduced loss of heavy metals.	Goulding 2016
WI8	Soil quality	+	Soils with higher pH generally have improved fertility, which is an indicator of good soil quality.	Goulding 2016
WI9	Flood management, water use	+/-	May positively or negatively affect evaporation and runoff generation processes at field/farm scales due to changes in soil structure which could affect water holding capacity.	Goulding 2016
WI10	Land cover and land use	0	No evidence found, unlikely to be a significant impact.
WI11	Biodiversity	+/-	The diversity of plant communities is influenced by soil pH, however net effects of pH changes are difficult to predict.	Olsson et al. 2009
WI12	Animal health and welfare	+	Reduced influence of liver fluke.	Mccann et al. 2010
WI13	Crop health	+	Improved crop growth associated with better crop health.	Janvier et al. 2007
WI14	Household income	+	No evidence found, a small positive impact can be expected from increased productivity.
WI15	Consumer and producer surplus	+	No evidence found, the potentially increased productivity can increase the producer surplus.
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	0	No evidence found, unlikely to be a significant impact.
WI18	Human health	+	Reduced availability of heavy metals in soils might lead to lower exposure via human consumption.	Podar and Ramsey 2005, Smith 1994
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.4 Anaerobic Digestion for manure processing ( MO4)

AD of manure can reduce the CH ₄ emission from the manure storage and can provide alternative energy sources thus providing further, indirect, GHG savings. In this assessment the focus was on small community scale (around 750 KW - 1 MW) AD digesting manure and additional biomass. The most critical factors that impact the environmental sustainability of AD plants are the feedstock type, feedstock source (the proportion of manure, the source of additional biomass, e.g. food waste or purpose-grown crops), digestate storage and how the digestate is spread to land (Whiting & Azapagic, 2014) which can vary greatly from plant to plant. Also it is important to consider what the existing land use is and whether there will be a significant land use change, or if existing waste products are being used, providing an additional benefit to their conventional use/storage.

Table 21 Wider impacts of MO4

Mitigation option:		Anaerobic digesters for manure processing ( MO4)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	-/0	AD plants concentrate organic wastes, concentrating distributed sources of NH 3 emissions. NH 3 emissions are dependent on site management practices concerning the handling, storage and treatment of organic wastes and the digestate. The storage of solid digestate and the aerobic treatment of liquid effluents are the greatest sources of NH 3 emissions. NH 3 emissions can be higher from digestate than from slurry if the storage tank is uncovered. Covered digestate storage can capture up to 80% of CH 4 and NH 3 from AD. A digestate cover that collects biogas provides additional energy production option. At spreading there are a number of competing factors compared with untreated slurry - greater total ammoniacal nitrogen and higher pH encouraging loss but lower dry matter which encourages more rapid infiltration and reduces loss. The literature is mixed, however, low NH 3 emission spreading techniques (see Section A1.8) can reduce NH 3 loss by 60%.	Bell et al. 2016, Moeller & Stinner 2009 Cumby et al. 2005 Reis ed. 2015, Whiting and Azapagic 2014 Amon et al. 2006, Battini et al. 2014, Chantigny et al. 2009, Pain et al. 1990
WI2	Air quality: NO x	-	Combustion of produced biogas in engine can increase NO x emissions, however this can be limited by improvements to biogas combustion technologies.	Battini et al. 2014
WI3	Air quality: PM	-	Emissions of NH 3 can lead to ammonium nitrate PM formation. AD, as a local combustion site, can shift the PM emissions from where the conventional power stations are.	Rotap 2012
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+/-	The literature is inconclusive, some experiments finding lower, others higher nitrogen leaching from digestate than from raw slurry. Best management practices can help mitigating negative effects.	Nkoa 2014
WI6	Water quality: Phosphorous	-	No evidence found, higher concentration of phosphorous in digestate than in raw slurry might pose risk of increased runoff.	Nkoa 2014
WI7	Water quality: other	0	No evidence found, unlikely to be a significant impact.
WI8	Soil quality	+/-	Grassland yields were found to be higher with digestate than with slurry, potentially as a result of enhanced plant available nutrients. Long term accumulation of micronutrients (e.g. copper, zinc) can occur, impeding soil quality.	Walsh et al. 2012 Nkoa 2014
WI9	Flood management, water use	0	No evidence found, unlikely to be a significant impact.
WI10	Land cover and land use	0	Varying results depending on previous land use and production systems used. Land use change away from conventional food crops is sometimes thought to be a concern, approximately 0.5% of UK arable cropping land is used for growing crops for AD and the current risk for intensive production of a single crop as monoculture is seen as low.	Börjesson & Tufvesson 2011 Röder 2016
WI11	Biodiversity	0	No evidence found, unlikely to be a significant direct impact on on-farm biodiversity.
WI12	Animal health and welfare	0	No evidence found, unlikely to be a significant impact.
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	+	Farmers' income: costs of installing plant can be expensive. Benefits for developers is available through incentive payments s, however changes to incentive schemes could impact this. Also using existing waste streams to meet on site energy demands can significantly lower bills. Income distribution: no significant impact is expected, though the distribution of the positive impact might be uneven as less prosperous farms might not be able to find the capital for the investment.	Röder 2016
WI15	Consumer and producer surplus	+	No evidence found, increased income could mean higher producer surplus.
WI16	Employment	+	Across the UK it is estimated that the number of jobs in biomass combustion and AD would be 35,000 - 50,000 by 2020. Employment potential is predicted to be higher than other renewable technologies due to additional elements of feedstock production, supply and plant operation.	McDermott 2012
WI17	Resource efficiency	++	AD recycles energy embedded in agricultural and other waste sources.
WI18	Human health	+/-	Increasing the amount of renewables can help mitigate the negative impacts of climate change on human health and air pollution. At the same time the more dispersed combustion can require additional effort in reducing pollution and there is an indirect negative effect from increased NH 3 emissions.	Haines et al. 2006
WI19	Social impacts	+	Community schemes could bring a sense of public engagement if done effectively.	Walker et al. 2010
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.5 Agroforestry ( MO5)

Agroforestry systems are multifunctional systems of woody vegetation (trees or shrubs) either combined with crops (silvoarable) or established on grazed pasture (silvopastoral). It also includes the use of trees and hedgerows as buffer zones. The trees and shrubs can be utilised for timber, fuel or fruit. The main GHG effect of agroforestry is the carbon sequestration in the vegetation and in the soil (Eory et al. 2015).

Table 22 Wider impacts of MO5

Mitigation option:		Agroforestry ( MO5)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	Trees are known to remove NH 3 from the atmosphere downwind of sources e.g. intensive livestock production.	Bealey et al. 2014
WI2	Air quality: NO x	+	Reduction of NO x emissions from fertiliser production and from soil, as a result of reduced use of nitrogen fertiliser per unit area.	Pacyna et al. 1991, Skiba et al. 1997
WI3	Air quality: PM	+	There is evidence for reduction of particulates and odour from shelterbelts.	Tyndall & Colletti 2007
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+	Extended root net of multiple species with different root architecture can reduce losses.	Bergeron et al. 2011
WI6	Water quality: Phosphorous	+	Potential reduction in run off as trees act as landscape level buffers.	Jose 2009
WI7	Water quality: other	+	Reduced use of agrochemicals as a result of smaller area of arable or grassland per unit area. Also increased presence of natural enemies of pests due to increased agrobiodiversity can lead to reduced pesticide use.	Stamps and Linit 1997
WI8	Soil quality	+	The literature suggests that agroforestry stores more carbon than agricultural systems but there is relatively little evidence in temperate systems. Possibly more benefit to soil carbon from trees planted into arable systems than trees planted in grassland. Additionally, soil erosion is reduced.	Upson & Burgess, 2013, Beckert et al. 2016
WI9	Flood management, water use	+	Potential improvement due to buffer strip effect.
WI10	Land cover and land use	+	Soil protection is likely to increase although very much depend on species combinations and management.	Mead 1995
WI11	Biodiversity	+	Increased species diversity in cropping can increase biodiversity.	McAdam et al. 2007
WI12	Animal health and welfare	+	Can provide shelter for animals - this can be shade in summer but also reduction of windchill in winter.	Karki & Goodman 2009
WI13	Crop health	+	Increased biodiversity and tree cover increases the presence of natural enemies to pests. This benefit can be enhanced by proper design.	Dix et al. 1995
WI14	Household income	0	No evidence found, unlikely to be a significant impact.
WI15	Consumer and producer surplus	0	No evidence found, unlikely to be a significant impact.
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	0	No evidence found, unlikely to be a significant impact.
WI18	Human health	+	The air and water quality improvements would have an indirect positive effect on human health, but no specific literature is found on this.
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	+	Landscape diversity, provision of recreation and possible use of native or rare trees, including production of fruit and nuts for local consumption.

A1.6 Incorporating more legumes in grass mixes and crop rotations ( MO6)

Legumes have symbiotic relationships with bacteria which allow them to fix atmospheric nitrogen and use this in place of nitrogen provided by synthetic fertilisers. They are also able to supply nitrogen to crops they are mixed with (e.g. clover-grass mixtures) or to a certain extent to subsequent crops in a rotation (e.g. peas in one year and cereals in the next).

Table 23 Wider impacts of MO6

Mitigation option:		Incorporating legumes in grass mixes and crop rotations ( MO6)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	NH 3 emissions will be reduced due to the reduction in nitrogen fertiliser applications. However, NH 3 emissions from the crop itself are likely to be higher than the baseline due to the residues of the legumes containing more nitrogen. The overall balance is likely to be positive.	Nett et al. 2015, Bath et al. 2006, Larsson et al. 1998, Mannheim et al. 1997
WI2	Air quality: NO x	+	Reduction of NO x emissions from fertiliser production and from soil, as a result of reduced nitrogen fertiliser applications.	Jensen and Hauggaard-Nielsen 2003
WI3	Air quality: PM	+	Indirect benefits resulting from the reduced nitrogen fertiliser production process. As the NH 3 emissions are likely to be reduced, there will be a reduction in the secondary PM formation.	Sutton ed. 2011
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	-	Increased risk of leaching during the post-harvest period from the biologically fixed nitrogen and crop residues compared to crops which receive fertilisers. This can be mitigated by having winter coverage of crops.	Jensen & Hauggaard-Nielsen 2003, Hauggaard-Nielsen et al. 2003, Engström & Lindén 2012
WI6	Water quality: Phosphorous	0	No evidence found, unlikely to be a significant impact.
WI7	Water quality: other	0	No evidence found, unlikely to be a significant impact.
WI8	Soil quality	+	Legumes improve soil fertility. Some legumes are deep rooting, and therefore can extract nutrients from deeper layers of the soil.	Jensen & Hauggaard-Nielsen (2003)
WI9	Flood management, water use	0	Unlikely to have a significant effect as long as leafy growth and rooting depths are similar to previous land cover.	Doorenbos and Pruitt 1977
WI10	Land cover and land use	+	Potential for legumes to be used as cover crops over winter.
WI11	Biodiversity	+	Increased diversity.	Jensen & Hauggaard-Nielsen 2003
WI12	Animal health and welfare	0	No evidence found, unlikely to be a significant impact.
WI13	Crop health	+	Increased use of break-crops in the rotations and thus reduce the survival of pests and pathogens is likely, though this effect will depend on the crops involved.	Jensen & Hauggaard-Nielsen 2003
WI14	Household income	0	On a rotation basis, farmers' income is unlikely to be affected. Nevertheless, it is perceived that growing grain legumes is a riskier crop to grow and may not be profitable for them. Income distribution: no significant impact is expected.	Reckling et al. 2016a
WI15	Consumer and producer surplus	0	No evidence found, unlikely to be a significant impact.
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	+	Reduced use of synthetic nitrogen fertilisers.
WI18	Human health	0	No evidence found, unlikely to be a significant impact.
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.7 Optimising the use of mineral nitrogen fertilizer ( MO7)

Optimising the use of mineral nitrogen fertiliser is assumed to mean that the fertiliser will be used more efficiently and therefore the losses from the system will be reduced. As well as reducing fertiliser applications rates, optimising the use of mineral fertiliser could also result from the optimising the method of applications.

Table 24 Wider impacts of MO7

Mitigation option:		Optimising the use of mineral nitrogen fertilizer ( MO7)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	Optimising the application of mineral fertilisers will reduce the emissions of NH 3. Emissions are dependent on fertiliser type, weather and soil conditions. In general applying with a regard to rates, times and placement, improved crop nitrogen uptake will mitigate NH 3 emissions, with minimal increases via the other loss pathways (e.g. nitrate leaching, denitrification to N 2O). Optimizing the method of spreading can also decrease NH 3 emissions e.g. decreasing the surface area of urea based fertilisers through band application, injection, incorporation decreasing the time that emissions can take place, i.e. through rapid incorporation or via irrigation; decreasing the source strength of the emitting surface, i.e. through urease inhibitors applying under cooler conditions and prior to rainfall (noting to avoid run-off) are associated with lower NH 3 emissions. Avoiding the application of fertilisers straight after grass cutting Emissions of NH 3 from urea-based fertilisers (5%-40% nitrogen loss as NH 3) are much greater than from other fertiliser types (e.g. ammonium nitrate, 0.5%-5% nitrogen loss as NH 3) due to an increase in pH. Switching from urea to ammonium nitrate fertiliser will reduce NH 3 emissions, with an effectiveness of around 90%. However, N 2O emissions might increase, especially when the ammonium-nitrate-based fertilisers are applied to moist or wet soils.	Bittman et al. 2014
WI2	Air quality: NO x	+	Reduction of NO x emissions from fertiliser production and from soil, as a result of reduced nitrogen fertiliser applications.	Pacyna et al. 1991, Skiba et al. 1997
WI3	Air quality: PM	+	Indirect benefits resulting from the reduced nitrogen fertiliser production process, as reduced NH 3 emissions results in less secondary PM formation. Also reduced NH 3 losses from soils resulting in reduced PM formation.	Sutton ed. 2011
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+	Nutrient use efficiency will be improved. This potentially leads to reduced nitrogen leaching due to reduced fertiliser losses (result of reduced fertiliser application and/or optimised application techniques).	Goulding et al. 2008
WI6	Water quality: Phosphorous	+	Nutrient use efficiency will be improved. This potentially leads to reduced multi-nutrient fertiliser applications and/or reduced losses due to optimised application techniques resulting in reduced losses.	Goulding et al. 2008
WI7	Water quality: other	0	No evidence found, unlikely to be a significant impact.
WI8	Soil quality	0	No evidence found, unlikely to be a significant impact.
WI9	Flood management, water use	0	No evidence found, unlikely to be a significant impact.
WI10	Land cover and land use	0	No evidence found, unlikely to be a significant impact.
WI11	Biodiversity	0	Unlikely to be an impact. Small indirect positive effect though reduced nitrogen emissions to air and water is expected.
WI12	Animal health and welfare	0	No evidence found, unlikely to be a significant impact.
WI13	Crop health	0	Unlikely to be an impact as it is likely to be a relatively small change in fertiliser applications. If fertiliser applications were to be reduced by 30-50%, there would probably be a negative effect on yield.
WI14	Household income	0	The net impact from fertiliser savings and time and money spent on advice/decision support tools/etc. can be either positive or negative, but it is likely to be insignificant.	Eory et al. 2015
WI15	Consumer and producer surplus	0	No evidence found, unlikely to be a significant impact.
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	0	The impact is highly uncertain as it will be affected by the utilisation of soil mineral, and any marginal changes in the nitrogen offtake.
WI18	Human health	+	Potential benefits resulting from reduced nutrient loss to air and water.
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.8 Low-emission storage and application of manure ( MO8)

Low emission storage of manure reduces NH ₃ (providing savings in indirect N ₂O emissions) and CH ₄ emissions via various methods, like reduced contact with air, reduced temperature or reduced pH. Low-emission manure spreading technologies ensure minimal contact of the manure with air, therefore reducing NH ₃ emissions. The retained Nitrogen during low-emission storage could increase NH ₃ and N ₂O losses when applied to the soil unless low-emission spreading techniques are implemented.

Table 25 Wider impacts of MO8

Mitigation option:		Low-emission storage and application of organic fertiliser ( MO8)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	++	Reduced with: band spreaders, injection and rapid incorporation. Slurry store covers can reduce NH 3 by 40-80%. Taller, narrower tanks (and deeper lagoons) have a lower surface area: volume ratio, which reduces NH 3. This also reduces the size and cost of covers, but increases the cost of storage as it increases the wall area and thickness. Slurry acidification reduces NH 3 but may present odour and human health risks.	NAAC 2010, Bittman et al. 2014 Van der Zaag et al. 2015
WI2	Air quality: NO x	0	No evidence found, unlikely to be a significant impact.
WI3	Air quality: PM	+	Reduced NH 3 emissions results in less secondary PM formation.	Sutton ed. 2011
WI4	Air quality: other	+ -	Reduced odour with band spreaders, injection and rapid incorporation. Most manure covers reduce odour. Slurry acidification may increase odour.	NAAC 2010, Van der Zaag et al. 2015
WI5	Water quality: Nitrogen leaching	+	Reduced with band spreaders, injection and rapid incorporation, but shallow injection can increase leaching on some soil types	NAAC 2010, Natural England 2015
WI6	Water quality: Phosphorous	+	Slurry injection and trailing shoe spreading reduce phosphorous losses.	Uusi-Kamppa and Heinonen-Tanski 2008, McConnell et al. 2013
WI7	Water quality: other	+	Slurry injection reduces the runoff of faecal microorganisms.	Uusi-Kamppa and Heinonen-Tanski 2008
WI8	Soil quality	+ -	Reduced soil compaction with umbilical systems. Slurry acidification may reduce soil pH (pers comm).	NAAC 2010
WI9	Flood management, water use	0	Minimal effects possible via changed soil structure, affecting infiltration and soil water conveyance.	Amrakh et al. 2016
WI10	Land cover and land use	0	No evidence found, unlikely to be a significant impact.
WI11	Biodiversity	0	No direct on-farm biodiversity effect is expected. Indirect positive effect though reduced air pollution is expected.
WI12	Animal health and welfare	+	Health effect from reduced pasture contamination with band spreading.	NAAC 2010
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	+/-	Farmers' income might be positively or negatively impacted (cost of equipment and operation versus reduced need for nitrogen fertiliers, reduced rainwater in the tanks if they are covered with an impermeable cover and reduced crop contamination with more precise manure application. Income distribution: no significant impact is expected.	Frelih-Larsen et al. 2014, Weiske et al. 2006, Van der Zaag et al. 2015
WI15	Consumer and producer surplus	0	No evidence found, unlikely to be a significant impact.
WI16	Employment	+	No evidence found, a small positive impact is possible in the form of higher skilled jobs required due to increased technical complexity of the methods.
WI17	Resource efficiency	+ -	Reduced NH 3 lead to increased nitrogen retention and lower requirement for synthetic nitrogen. Slurry acidification may increase corrosion rates and shorten life of slurry tanks (pers comm 2016).
WI18	Human health	- +	Slurry acidification may increase risk to farmers, via exposure to strong acids and H 2S. Potential benefits resulting from reduced nutrient loss to air and water.	Van der Zaag et al. 2015
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.9 Improving livestock health ( MO9)

Diseases can lead to impacts on livestock performance such as (Skuce et al. 2016): (i) fewer units of product e.g. milk, meat or wool; (ii) animals taking longer to reach their target market weight; (iii) delayed onset and reduced quality of production e.g., for milk; (iv) lost production i.e. lambs or calves aborted due to infection; (v) premature culling; (vi) waste of animal products condemned at abattoir; (vii) reduced reproductive performance; or (viii) premature death of animals. Treating and preventing diseases therefore tend to increase productivity and lead to decreases in the emissions intensity of the meat, milk or eggs. For example, treating for diseases that affect feed conversion efficiency (such as liver fluke and parasitic gastroenteritis) will lead to a reduction in the amount of feed consumed and the amount of volatile solids and nitrogen excreted per kg of output, which will in turn reduce emissions associated with feed production and manure management. Health can be improved through preventative controls (such as changing housing and management to reduce stress and exposure to pathogens, vaccination, improved screening and biosecurity, disease vector control) and curative treatments such as antiparasitics and antibiotics. The wider impacts of improving livestock health therefore depend on the specific species, system and, health challenge and control option. The table below seeks to illustrate the wider impacts that could arise from improving health, rather than provide a comprehensive analysis.

Table 26 Wider impacts of MO9

Mitigation option:		Improving livestock health ( MO9)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	Measures that improve feed conversion efficiency (either at the animal or flock/herd level) will reduce the amount of nitrogen excreted per kg of meat/milk/eggs produced, leading to reductions in NH 3 from manure management and direct deposition of nitrogen. Examples of diseases with a significant impact on feed conversion efficiency include fasciolosis and parasitic gastroenteritis (see Skuce et al. 2016, Annex 2).	Skuce et al. 2016
WI2	Air quality: NO x	0	No evidence found, unlikely to be a significant impact.
WI3	Air quality: PM	0	No evidence found, unlikely to be a significant impact.
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+	See NH 3
WI6	Water quality: Phosphorous	+	Measures that improve feed conversion efficiency (either at the animal or flock/herd level) will reduce the amount of phosphorous excreted per kg of meat/milk/eggs produced.	Skuce et al. 2016
WI7	Water quality: other	-	Potential issues of aquatic ecotoxicity with some measures, e.g. SP dips.	Beynon 2012
WI8	Soil quality	0	No evidence found, unlikely to be a significant impact.
WI9	Flood management, water use	0	No evidence found, unlikely to be a significant impact.
WI10	Land cover and land use	0	No evidence found, unlikely to be a significant impact.
WI11	Biodiversity	-	Potential negative impacts via control of wild animal/plants and habitat alteration to reduce vector/pathogen populations (e.g. badger culling to reduce TB transmission or field drainage to reduce mud snail populations, which act as a vector for liver fluke). Further negative impacts of medication to dung invertebrates and indirect impacts further up the food chain.	SCOPS 2016 Adler et al. 2016 http://www.drbeynonsbugfarm.com/CMSDocuments//Fact%20sheet%202_Parasiticides_Aug%202016.pdf
WI12	Animal health and welfare	+/-	Most measures should lead to improved animal welfare, however there are potential inter-temporal effects - over use of antimicrobials could lead to resistance and reduced treatment efficacy in the future.	Oliver et al. 2011
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	0	Farmers' income: No significant impact expected in general, though cases might vary widely depending on the disease, treatment and transfer payments. Income distribution: no significant impact is expected.
WI15	Consumer and producer surplus	0	No significant impact expected in general, though cases might vary widely depending on the disease, treatment and transfer payments.
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	+	Improved health should lead to improved resource use efficiency.
WI18	Human health	+/-	Negative impact via increased antimicrobial resistance. Potential positive impact via reduced human exposure to zoonoses (e.g. salmonella, toxoplasmosis, chlamydia).	Oliver et al. 2011
WI19	Social impacts	0	No evidence found, unlikely to be a significant impact.
WI20	Cultural impacts	0	No evidence found, unlikely to be a significant impact.

A1.10 Reduced livestock product consumption ( MO10)

Reduced livestock product consumption can contribute to GHG mitigation as livestock products are the most GHG intensive components of the diet (Steinfeld et al. 2006). Diet related emissions of UK high meat-eaters were found to be 28%, 54%, 84%, 89% and 149% higher than medium meat-eaters, low meat-eaters, fish-eaters, vegetarians and vegans, respectively (Scarborough et al. 2014).

Assuming no change in exports, GHG emissions (including UK and overseas emissions) would be reduced by 19% with a 50% reduction in livestock consumption in the UK (-40% dairy, -64% meat) (Audsley et al. 2011). That paper reported that net effect would greatly depend on the alternative land use and the substitution in the diet. Substitution of red meat with white meat could reduce emissions by 9%, while reducing white meat consumption by 50% would mitigate 3.3% of the related GHG emissions. At the same time reducing livestock product consumption by 50% would decrease the land area used for food production domestically and overseas by 28-48%, mostly releasing UK grassland areas from food production. If the red meat in the diet were replaced with white meat, the grassland area would be reduced somewhat further, but the increased demand for tillable land both in the UK and abroad would overweight this gain, in total releasing 25-44% land. Reducing white meat consumption only would have only a minor positive effect on land use. The study estimated that currently 36% of the UK food consumption related GHG emissions occur overseas. With the study's assumption on constant proportion of production, exports and imports most of the GHG effects happened in the UK.

However, due to exports and imports, some of the GHG mitigation would manifest abroad. The gross value added of agriculture and food manufacturing (not including wholesale, retail and catering) was £5.4bn in 2014 (Office for National Statistics 2015), while in 2010 food exports and food imports were £4.5bn and £1.1bn, respectively (the former including £4bn drink export) (Scottish Government 2012). 47% of the Scottish primary produce (agriculture and fishery) was purchased by non-Scottish purchasers (including rest of the UK) (Scottish Government 2012). These statistics show that trade with the rest of the UK and abroad is important for the Scottish agricultural and food sector, though these numbers do not reveal how a shift in consumption patterns would impact on exports, imports and ultimately on domestic production.

The domestic environmental impacts and GHG effects of reduced livestock product consumption are dependent on the strength of the relationship between domestic consumption and domestic production. For example, domestic production might be less affected by reduced livestock consumption if export markets for livestock products are available and most of the increase in fruit and vegetable consumption would be provided by imports. Though consumption based environmental metrics are likely to change significantly with a change in the diet, a large proportion of these impacts might manifest abroad, leaving the wider impacts related to domestic production less affected. Wolf et al. (2011) modelled three alternative, reduced meat diets for Europe and found that though first order effects include, amongst other changes, a drop of 44% in cattle production, second order effects only show a 9% reduction. Similar effects can be seen in GHG mitigation and in all other environmental impacts analysed, just as in a similar study by Tukker et al. (2011).

One of the major co-benefit of reduced meat and dairy product consumption can be improved human health (McMichael et al. 2006). However, it is important to note that a healthy diet is not necessarily associated with lower GHG emissions, as the overall GHG effect depend on the substitutions made and the total calorie intake goals. Vieux et al. found (2012) that an isocaloric substitution of meat consumption (capping it at 50g day ^-1) with vegetables and fruits did not reduce the GHG emissions in France, and analysing dietary recommendations in the United States showed that following the 2010 US Dietary Guidelines (even with a reduced total caloric intake) would increase GHG emissions (Tom et al. 2015).

Summarising, the domestic GHG and environmental impacts and health impacts of this MO will heavily depend on:

• The reduction in livestock product consumption regarding changes in the share of dairy, white meat and read meat products,
• Whether calorie intake is reduced as well or not,
• Substitution of the livestock products with cereals, vegetables, fruits, oils/nuts/seeds, etc. (with particular attention to products which might have negative environmental impacts, like palm oil and soya, or can be less healthy, like more processed food),
• Reaction of exports, imports and domestic production to consumption change,
• Alternative use of released land and
• Re-structuring of the supply chain in order to reduce negative economic impacts.

Table 27 Wider impacts of MO10

Mitigation option:		Reduced livestock product consumption ( MO10)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	+	Acidification and eutrophication are reduced with healthy diets in Europe due to reduced nitrogen pollution; when only income effects are included the benefits are much higher than when second order rebounds (economy-wide reactions on change in demand for foodstuffs) are considered. Isocaloric replacement of 25-50% of livestock consumption with plant-based products in the EU would reduce nitrogen emissions by 40%.	Tukker et al. 2011 Westhoek et al. 2014
WI2	Air quality: NO x	0	No evidence found, effects can depend on substitution (as related to transport and processing).
WI3	Air quality: PM	0	No evidence found, effects can depend on substitution (as related to transport and processing).
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	+	Acidification and eutrophication are reduced with healthy diets in Europe; when only income effects are included the benefits are much higher than when second order rebounds (economy-wide reactions on change in demand for foodstuffs) are considered.	Tukker et al. 2011
WI6	Water quality: Phosphorous	+	Acidification and eutrophication are reduced with healthy diets in Europe; when only income effects are included the benefits are much higher than when second order rebounds (economy-wide reactions on change in demand for foodstuffs) are considered.	Tukker et al. 2011
WI7	Water quality: other	-	Ecotoxicity (mostly related to pesticide use from higher consumption of vegetable food) increases with healthier diets in Europe.	Tukker et al. 2011
WI8	Soil quality	+/-	No evidence found, impacts would greatly depend on alternative use.
WI9	Flood management, water use	+/-	The impact on water scarcity varies depending on the diet, though most of the impact happens outwit of the UK (not including knock-on effect on land use)	Hess et al. 2015
WI10	Land cover and land use	+	Isocaloric replacement of 25-50% of livestock consumption with plant-based products in the EU would reduce per capita land use by 23%. In Scotland the most substantial impact would be a move from grasslands towards alternative uses (e.g. forestry).	Westhoek et al. 2014
WI11	Biodiversity	+/-	No evidence found, impacts would greatly depend on what land areas will be released (e.g. extensive or intensive grasslands, arable land) and on the alternative use (e.g. sustainable forestry, arable production or bioenergy production).
WI12	Animal health and welfare	+/-	No evidence found. The effect could depend on consumer demand for animal welfare and the economics of intensification vs extensification of livestock production.
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	+/-	Substituting livestock products with other food products might result either in savings or higher food expenses for the consumers. If GHG emission-based food taxes were introduced, also resulting in lower meat consumption (highest tax rates on beef, coffee drinks, lamb, cheese, animal fats, pork, other meat, bread, tea and cocoa), all socio-economic classes would reduce their food intake, and the tax burden would fall disproportionately on households in the lowest socio-economic class. Household income of those in the livestock supply chain could decrease.	Kehlbacher et al. 2016
WI15	Consumer and producer surplus	+/-	The impacts are negative on the livestock related parts of the food chain while positive on producers and processors of plant-based food products and also on some other sectors, like transport. As much of Scotland's agricultural land is only suitable for livestock but not vegetable/grain production, the overall effects - as far as Scottish consumption will affect Scottish production - are more likely to be negative.	Lock et al. 2013
WI16	Employment	+/-	No evidence found, likely to follow production changes described in the previous point.
WI17	Resource efficiency	+	As livestock numbers are reduced part of the ecological pyramid related to human consumption is eliminated, therefore resource use efficiency increases (e.g. nitrogen use efficiency of the European food system can increase from 18% to 41-47%.	Westhoek et al. 2014
WI18	Human health	++	Reductions in livestock production consumption leads to 2,000 - 37,000 avoided premature death per annum in the UK, depending on the diet changes (modelled diet scenarios were based on the Committee on Climate Change Fourth Carbon Budget). Population aggregate risks in the UK would be reduced 3% to 12% for coronary heart disease, diabetes mellitus and colorectal cancer if meat consumption is reduced. Following the UK dietary guidelines would avoid 33,000 premature death per annum from cardiovascular diseases and cancer in the UK (4,300 in Scotland). Human toxicity is reduced with healthier diets in Europe.	Scarborough et al. 2012a Aston et al. 2012 Scarborough et al. 2012b Tukker et al. 2011
WI19	Social impacts	+/-	No evidence found, effects would depend on larger and smaller scale changes in the food supply chain.
WI20	Cultural impacts	+/-	No evidence found, effects might arise in food culture and also from the induced land use change.

A1.11 Afforestation ( MO11)

Afforestation has been and can further be a major contributor to reducing the net GHG emissions by sequestering carbon in the soil and as woody biomass.

Forestry practice is covered by the UK Forestry Standard (Forestry Commission 2011). Additionally, the UK Woodland Assurance Standard ( UKWAS 2008) contains explicit commitments to low impact silvicultural systems which may include, but is not exclusively restricted to, continuous cover forestry operations. Certification bodies such as the Forestry Stewardship Council and Programme for the Endorsement of Forest Certification also provide accreditation and endorsement of sustainably managed forests. Adherence to standards will ensure that potential adverse impacts are minimised.

Table 28 Wider impacts of MO11

Mitigation option:		Afforestation ( MO11)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	++	NH 3 is captured by trees downwind, which can be of particular importance near livestock operations.	Patterson et al. 2008, Famulari et al. 2015, Bealey et al. 2014
WI2	Air quality: NO x	++	A number of studies from around the world which are transferable to Scotland show that trees can remove NO x and improve air quality in both urban and rural areas.	Cohen et al. 2014, Nowak et al. 2006
WI3	Air quality: PM	++	Reduced concentration of PM 10 (and other pollutants). Coniferous species and broadleaf trees with hairy leaves have a greater effectiveness at capturing particles than other broadleaf trees.	Cohen et al. 2014, Powe and Willis 2004 Beckett et al. 2000
WI4	Air quality: other	+	Reduced concentration of carbon monoxide and sulphur dioxide. Urban trees generally reduce ozone and carbon monoxide; evidence on similar effects of forests has not been found.	Cohen et al. 2014, Powe and Willis 2004 Nowak et al. 2000, Nowak et al. 2006, Taha 1996
WI5	Water quality: Nitrogen leaching	+	Afforestation of arable land can reduce nitrogen leaching although nitrogen leaching can occur from mature forests which have achieved full canopy cover. The amount of nitrogen leaching depends on tree type, with higher leaching rates from broadleaf woodland. Harvesting can lead to short time releases of nitrogen although this depends on harvest method, and fluxes may be less than from arable land.	Hansen et al. 2007, Bastrup-Birk & Gundersen 2004, Reynolds & Edwards 1995 Elberling 2006 Nisbet et al. 2011
WI6	Water quality: Phosphorous	0	Tree planting and harvesting have the potential to release Phosphorous into waterbodies, however woodland buffer strips along water courses can reduce erosion and phosphate leaching. Forestry operations are carried on in accordance with the Forest and Water Guidelines it is unlikely to be an effect.	Nisbet et al. 2011, Stevenson et al. 2016 Nisbet 2002
WI7	Water quality: other	- 0 - - +	Although afforestation has the potential to produce adverse impacts on water quality, where forests are planted and managed in accordance with the UK Forestry Standard adverse impacts are likely to be avoided. However potential issues associated with afforestation are listed here to highlight the importance of ensuring that the Forest Standard is followed. Changes in algal populations in lakes in Ireland related to afforestation in catchments in Ireland which were more than 20% forested, but no effect on less afforested catchments. No change in turbidity, water colour, or iron or manganese concentrations in water in two afforested catchments in Argyll where forestry operations are carried on in accordance with the Forest and Water Guidelines. Badly located forests, particularly conifers on poorly buffered soils can cause acidification by scavenging atmospheric sulphur and nitrogen. Forests close to rivers can provide shade help rivers to adapt to climate change, but some species can cast heavy shade and lowers water temperature excessively if planted close to river banks. Poor practice during planting and harvesting can release sediment into watercourses. Afforestation around arable fields can reduce spray drift of pesticides into watercourses by 60 - 90 %.	Stevenson et al. 2016 Nisbet 2002 Nisbet et al. 2011 Nisbet et al. 2011 Nisbet et al. 2011 Nisbet et al. 2011
WI8	Soil quality	+/-	Afforestation on mineral soils can increase soil carbon stocks. However drainage and afforestation of organic soils releases soil carbon. The UK Forestry Standard does not permit afforestation on organic soils and therefore mitigates this risk.	Bradley et al. 2005, Grüneberg et al. 2014
WI9	Flood management, water use	++	There is evidence that trees (coniferous to a larger degree than broadleaved) use/intercept more water than shorter vegetation types Infiltration rates may be significantly enhanced (and thus runoff reduced) where grazed pasture is planted with woodland Floodplain woodland may lead to significant increases in flood storage and flood peak travel times	Bosch and Hewlett 1982 Marshall et al. 2014 Thomas and Nisbet 2007
WI10	Land cover and land use	+	Afforestation inherently involves a change in land use and in general considered as a positive outcome. However, opportunity costs of the previous land use need to be considered. For example afforestation of prime agricultural land would result of less of agricultural production, whereas afforestation of semi-natural grassland would cause much less loss of existing income. Afforestation alters landscape value. Public perception of landscape change is dependent on the proposed change and knowledge of the previous land use history.	Hanley et al. 2009, Habron 1998
WI11	Biodiversity	+/-	The effect on biodiversity will depend on the type of tree planting and the previous use of the afforested land. UK Forestry Standards require the conservation and enhancement of biodiversity in afforestation and forest management.	Forestry Commission 2011
WI12	Animal health and welfare	-	Probably little effect in most instances, although afforestation on peatlands might increase tick abundance.	Gilbert 2013
WI13	Crop health	0	No evidence found, unlikely to be a significant impact.
WI14	Household income	+/-	Land owners' income: depends on the balance of the opportunity costs of the land and any government payments. Income distribution: Likely to depend on the balance of employment opportunities associated with afforested land compared to those associated with the previous land use.
WI15	Consumer and producer surplus	+/-	Will reduce agricultural production, but increase production of timber products.	CJC Consulting 2013
WI16	Employment	+/-	Potential to increase employment in rural Scotland in forestry activities, timber processing and through associated leisure and tourism activities. However will displace some jobs in other land based sectors e.g. agriculture.	CJC Consulting 2013
WI17	Resource efficiency	+	The produced wood can be used for fuel or as construction material.	CJC Consulting 2013
WI18	Human health	+	Woodlands can enhance recreational opportunity, encourage people to exercise more and improve quality of life. Forests provide pest and disease regulation, noise regulation and soil, air and water regulation; all improving contributing to positive human health outcomes. Additionally, woodlands improve physical and mental health via providing recreational space. Woodland has positive impacts on health because it can absorb pollutants, encourage exercise and reduce stress.	Ambrose-Oji et al. 2014 Bateman et al. 2011 Mourato et al. 2010, Nowak et al. 2013, Tiwary et al. 2009
WI19	Social impacts	+	Woodlands located close to settlements can provide space for community activities.	Ambrose-Oji et al. 2014
WI20	Cultural impacts	+/-	Woodlands can enhance recreational opportunity and can contribute to landscape and aesthetic amenity. Recreational demand varies to the nature of the forest recreation site such as the size and type of woodland, facilities and the recreational activities available on site. Woodland also indirectly influences recreation, for example: via effects on water quality, affecting recreational fishing, swimming or boating, air quality (through health effects or visibility), climate/temperature (through shading, cooling and shelter from extreme weather) and biodiversity (through bird watching or nature viewing). Afforestation might negatively impact landscape, historic and recreational values of the land in certain places; afforestation projects should follow the UK Forestry Standards, and "should be designed […] to take account of the historical character and cultural values of the landscape. […] to take account of landscape designations, designed landscapes, historic landscapes and the various policies that apply." Those involved in activities related to the current use of land which is to be afforested may view afforestation as a challenge to the cultures associated with those land uses e.g upland farming and sporting activities.	Ambrose-Oji et al. 2014, Jones et al. 2010, Bateman et al. 2011, Forestry Commission 2011

A1.12 Peatland restoration ( MO12)

Scotland has large areas of peatland which are significant carbon reservoirs, storing 1,780 Mt of carbon (Smith et al. 2007). However, land management activities have resulted in 70 % of blanket bog (Artz et al. 2014) and 90 % of raised bog in Scotland (Lindsay and Immirzi, 1996) are estimated to be degraded with the result that they have switched from being GHG sinks to GHG sources. Peatland restoration which raises the water table and restores semi-natural vegetation can reduce the CO ₂ emissions associated with the degradation of peatlands and may return peatlands to being net GHG sinks. Peatland restoration is likely to improve the biodiversity of these international important habitats and is likely to have complex interactions with hydrology and landscape value.

Table 29 Wider impacts of MO12

Mitigation option:		Peatland restoration ( MO12)
Impact		Direction/ magnitude	Notes	References
WI1	Air quality: NH 3	0	No evidence found, unlikely to be a significant impact.
WI2	Air quality: NO x	0	No evidence found, unlikely to be a significant impact.
WI3	Air quality: PM	+	Could be a small reduction in airborne PM from reduced heather burning and eroding peat.
WI4	Air quality: other	0	No evidence found, unlikely to be a significant impact.
WI5	Water quality: Nitrogen leaching	-	Rewetting of peatland sites can increase nitrogen leaching particularly in the early years of restoration. The risk is increased where fertiliser has been applied or where trees are felled during restoration.	Similä et al. 2014, Menberu et al. 2015, Kieckbusch and Schrautzer 2007
WI6	Water quality: Phosphorous	-	Rewetting of peatland sites can increase phosphorous leaching particularly in the early years of restoration. The risk is increased where fertiliser has been applied or where trees are felled during restoration.	Similä et al. 2014, Menberu et al. 2015, Kieckbusch and Schrautzer 2007, Cummins and Farrell 2000
WI7	Water quality: other	- +	Rewetting of peatland sites can increase organic carbon leaching, particularly in the early years of restoration. In the longer term peatland restoration can reduce organic carbon leaching in some catchments. Removing dissolved organic carbon from water increases water treatment costs.	Similä et al. 2014, Menberu et al. 2015, Kieckbusch and Schrautzer 2007 Armstrong et al. 2010 Wallage et al. 2006
WI8	Soil quality	++	Reduced carbon loss from degraded peat is an intended outcome of peatland restoration.	Lilly, et al. 2009
WI9	Flood management, water use	Flood management +/- Water use --	Drainage speeds-up flow, which can lower water tables. This increases the ability of the drained area to absorb rainfall, which can help reduce flood risk downstream. Net effects are difficult to measure. Impacts depend on topography, layout of drainage or other management intervention and location in the headwater catchment with respect to the drainage network. So in some cases blocking peatland drains will reduce flood risk, in other cases it can increase flood risk. Re-vegetating wetlands reduces the speed of overland flow and potentially reduces the flood peak during some events. There is strong evidence that wetlands evaporate more water than other land types, such as forests, savannah grassland or arable land. Many studies of wetlands conclude that wetlands reduce the flow of water in downstream rivers during dry periods (relevant for Scottish dry spells which are likely to become more frequent as a result of climate change).	Acreman and Holden 2013 Bullock and Acreman 2003
WI10	Land cover and land use	+/-	Change from afforested plantation forestry to semi-natural peatland alters landscape value. Public perception of landscape change is dependent on the proposed change and knowledge of the previous land use history. Deforestation limits the use of peatlands for timber production. It allows peatlands to increase carbon sequestration in peat, but this has to be offset against reduced in carbon sequestration in timber.	Hanley et al. 2009, Habron 1998
WI11	Biodiversity	++	Scotland holds 13 % of the world's peatlands which are globally important habitats, although 80 % of Scottish peatlands are currently degraded. Near-natural peatlands are protected under the Ramsar convention and the EU habitats Directive. Peatland restoration aims to restore natural peat forming vegetation.	Ramsar 1971
WI12	Animal health and welfare	+	Tick numbers are reduced when afforested peatlands are restored, potentially reducing tick-born diseases in nearby livestock.	Gilbert 2013
WI13	Crop health	-	Could be a small negative effect on crop health if cropland on drained peat was rewetted (not full restoration but higher water table under arable to reduce carbon loss), although more applicable to England than Scotland as the area of cropland on drained peat in Scotland is small (around 8.6 kha) and the focus of peatland restoration is on afforested peat or semi-natural grassland.
WI14	Household income	+/-	Land owners' income: depends on the balance of the opportunity costs of the land and any government payments. Income distribution: no evidence, and unlikely to be an important impact
WI15	Consumer and producer surplus	0	No evidence, but the impact might be important. Regarding consumer surplus indirect impacts of restoration on water quality may be worth investigating in more detail - specifically impacts on water treatment costs. Regarding producer surplus, impacts depend on previous land uses, which primarily include forestry, grouse and deer management, grazing of livestock (sheep). Impacts will depend on the scale of restoration and other local factors. There is anecdotal evidence that land managers have opted for restoring parts of their lands because of positive side-effects on production-related activities (Andrew McBride, personal comm. 6 June 2016). For example, blocking drains and gullies may decrease mortality rates amongst grouse chicks. Hence, the assumption of positive opportunity costs of restoration may not hold in all cases and requires further investigation.	Glenk et al. 2014
WI16	Employment	0	No evidence found, unlikely to be a significant impact.
WI17	Resource efficiency	0	No evidence found, unlikely to be a significant impact.
WI18	Human health	+/-	Human health may benefit from reduced tick numbers, particularly with the increasing prevalence of the tick-borne infection Lyme's disease. Increased incidence of midges is possible if restoration takes place in proximity to popular camping grounds or hiking paths. Impacts on health may also be related to recreational opportunities.	Gilbert 2013 Martin-Ortega et al. 2014
WI19	Social impacts	+	No evidence found, but the impact might be important, especially for rural communities that engage in peatland restoration activities, as well as communities that have strong traditional ties to peatlands (e.g. crofting communities)
WI20	Cultural impacts	+/-	No evidence, but the impact might be important. Peatlands provide important cultural services, though the current provision of these services cannot be easily transferred to assess the impacts that peatland restoration will have. E.g. hunting is an important benefit currently but restoration via reduced burning activities may be detrimental to this activity. Accessibility might be an important factor in recreational benefits.